In 1419, Barbaro was appointed senator of the Republic of Venice.[16][2] He was elected governor of Como in 1421, though he declined the post. Later that year he accepted the governorship of Trivigi.[13] He served as governor of Vicenza in 1423, of Bergamo in 1430, and of Verona in 1434.[12][2][16][17]

In 1426 Barbaro was sent as a special envoy to the Papal Court to try to persuade Pope Martin V to ally with Venice against Milan.[3][16][17] In 1428, the Pope assembled a congress at Ferrara, which ended the war, with Francesco Barbaro being one of Venice’s representatives there.[17] That year Barbaro also served as ambassador in Ferrara and Florence. In 1433, Barbaro represented Venice at the court Emperor Sigismund in Bohemia, where he and the other envoys were knighted by the Emperor.[3][16][17] At Emperor Sigismund’s request, Francesco Barbaro attempted to soothe relations between the Emperor and the Hussites.[17]Eugenius IV also employed Barbaro in his negotiations with the Emperor.[17]

As governor of Brescia, from 1437 to 1440, Francesco Barbaro was able to reconcile the two rival factions of Avogadri and Martinenghi and he attained a great reputation in his defense of the city against the forces of the Duke of Milan, led by Niccolò Piccinino.[12][2][16] Barbaro's success was commemorated by Giovanni Battista Tiepolo in his painting The Glorification of the Barbaro Family.[18]

Some of his letters and speeches were published for the first time in Brescia in 1728 under the title of Evangelistae Manelmi Vicentini Commentariorum de Obsidione Brixiae ann. 1438.[2] Among the people he corresponded with were Alberto da Sarteano, Guarino Guarini,[25] and Ludovico Trevisan.[15] Many of his letters were published by Bernard Pez in Brescia in 1753.[12][19] He may have been the author of a history of the Siege of Brescia.[12][2][19]